A suspect has been arrested in France in connection with the May 24 shooting at the Jewish Museum in Brussels that killed three people.

Mehdi Nemmouche, 29, a French citizen, was detained at a bus station in the southern French city of Marseille on Friday and had a Kalashnikov assault rifle and another gun with him, a French police source said on Sunday. Nemmouche was in possession of a Kalashnikov rifle and a handgun similar to the ones used in the attack on May 24, sources said.

An official with the prosecutor's office says the suspect has been handed to anti-terrorist investigators and could be held at least through Tuesday under French counterterrorism law, the AP reported.

A passer-by places flowers at the entrance of the Jewish Museum in Brussels, Belgium, May 27, 2014.

Nemmouche is originally from Roubaix in northern France and is believed to have traveled to Syria in 2013 to join Islamist fighters.

The shooting by a lone gunman killed three people outright - an Israeli couple and a Frenchwoman, while the fourth victim, a 24-year-old Belgian man, was left clinically dead.

Police had released explicit video of the attack, showing a gunman, whose face is not visible under a cap, entering the Jewish museum and taking a Kalashnikov from a bag and opening fire.

French media said Nemmouche was arrested as part of random, drug-related checks at Marseille's bus terminal. Local media also reported that he had in his bag press clippings about the Brussels Jewish museum shooting.

Soulifa Badaoui, who worked as a lawyer for the suspect in the past, told BFM TV Nemmouche was not religious at the time. Asked what role religion played for him then, she said: “None, this was absolutely not part of his personality, he was not observant at all.”

“For me, he was in no way a young man who seem pre-destined to commit this sort of act,” Badaoui said.

Motive behind attack

Anti-Semitism is strongly suspected as the motive behind the attack.

European Jewish Congress President Moshe Kantor praised French and Belgian authorities for the arrest, saying there was a need to clamp down on the spread of hate crimes, especially by those hardened by bloodshed in places like Syria.

“ … For too long authorities in Europe have acted speedily after the fact. It is now time for all to turn attention and set as the highest priority the prevention of these vicious crimes,” he said in a statement.

Jewish community officials have drawn parallels between the Brussels shooting and the 2012 killing of four Jews at a school in France by an al Qaeda-inspired gunman, Mohamed Merah.

Security around all Jewish institutions in Belgium was raised to the highest level after the shooting, and French authorities also stepped up security after two Jews were attacked the same day as they left a synagogue in a Paris suburb wearing traditional Jewish clothing.